In the past, a mobile object monitoring system is provided to monitor a mobile object such as construction machine. This type of the mobile object monitoring system is equipped with a mobile object monitoring device mounted on a target mobile object to collect and send information about the mobile object, such as position, battery voltage, and fuel level, to a control unit.
According to the mobile object monitoring system, even the mobile object is positioned in a remote working area, the control unit is able to keep track of conditions of the mobile object such as operational statuses and judgment of maintenance necessities, based on the information received by the control unit. Accordingly, the mobile object is quickly treated even if a problem is found in the mobile object.
Usually, a collection process of information by the above mentioned mobile object monitoring device is continued while an engine is not running. However, if the mobile object monitoring device continues the collection process at a same operation rate when the engine is not running, a battery is subjected to a large load, thereby causing such problem that the engine is not restarted after the engine is turned off for a long time.
Therefore, a system which prolongs a battery life by reducing the operation rate of the information collection process of the mobile object monitoring device when the engine is off state for a predetermined period is provided in the past. According to this conventional technique, the battery load is reduced as much as possible, since the operation rate of the information collection process of the mobile object monitoring device is reduced, that is, a resting time of the mobile object monitoring device is increased, when the engine is off state for a long term. Accordingly, a capacity of restarting the engine is secured even thought the engine is off state, and a continuous monitoring of the mobile object is allowed (for example, see Patent Document 1).
Patent Document 1: Japanese Patent Application Laid-Open No. 2003-27528